1. Field of the Invention
The present invention relates to an electronic device composed of a printed circuit board including a semiconductor chip mounted thereon.
2. Description of the Prior Art
In order to protect an IC chip exposed on the surface of a printed circuit board from moisture or impurities, it is indispensable to seal the IC chip with resin or a can.
Prior techniques of this type are described in Japanese Utility Model Publication No. 55-47065, for example.
In what follows, a prior art printed circuit construction will be described with reference to FIG. 1.
As shown in FIG. 1, an IC chip (4) is fixedly mounted on a printed circuit board (1) with use of an adhesive (5). The IC chip (4) is electrically connected with a conductive layer (2) via metal wires (6). An insulating frame (7) is fixedly mounted onto the conductive layer (2) with an adhesive (8). The frame (7) is filled therein with a sealing material (9) to seal the IC chip (4) and the periphery thereof.
For the sealing material (9), an epoxy resin pellet prepared for example by cold molding or pressure molding is melted in the frame (7), which frame is then filled therewith. The melted resin is thereafter hardened.
As described above, such prior printed circuit devices necessitate some processes of mounting of the frame (7), throwing of the resin pellet into the frame (7), and melting and hardening of that resin pellet. This increases the cost of manufacture of the device.